Electric-arc lamp



(No Model) 2 sheets-sheet 1. G. PPANNKUGHE.

ELECTRIC ARG LAMP.

No. 393,447. Patented Nov. 27, 1888.

Fig'. l-

. l l i WITNESSES INVENTOR:

M coyneys, r 4 E (No Model.) 2 Sheets-Sheet 2. G. PFANNKUGHE.

ELECTRIC ARG LAMP. No; 888,447. Patented Nov. 27, 1888.

INVENTOR WITN 1588158 1 www @www f//wv WM5-w. I By hzl zzolffzeys,

UNITED STATES PATENT @Errea GUSTAV PFANNKUCHE, OF EXETER, FEW HAMPSHIRE.

ELECTRIC-ARC LAM P.

SPECIFICATION forming part of Letters lPatent No. 393,447, dated November 27, 1888.

Serial No. QI'LSSL (No model.)

To @ZZ whom, 17mzj concern:

Be it known that I, GUsTAv PEANNKUCHE, a resident of Exeter, in the county of Rockingham and State of New Hampshire, have invented certain new and useful Improvements in Electric-Arc Lamps, of which the following is a specification.

Thisinvention relates most particularly to arc lamps of the rack-and-pinion class, or those wherein the carbon-holder is provided with rack-teeth which engage the pinion of a slow-movement gear controlled by electromagnets for regulating the length of the arc and determining the feed of the carbons as they consume.

In lamps of this character heretofore made the slow-movement gear for retarding the deA scent of the carbon-holder,as well as the releasing mechanism, has been made bodily movable up and down, boing connected to the magnet or solenoid by which the are is established, so that in the operation of striking the arc the slow-movement gear has been lifted and has been the medium for lifting the earborrholder. This construction has the disadvantage that the lamp is liable to respond too quickly to sudden or accidental fluctuations inthe volume of the current, regardless of the length of the are. This annoying propensity of such lamps, known as pumping77 accounts for much of the flickering and hissing attendant upon their operation. To overcome this defeet some very complicated regulating mechanisms have been invented. The simplest eX- pedient for reducing pumping is the attachment of a dash-pot7 to the frame carrying the gearing; but this overcomes one defect in a measure only by introducing another, since dash-pots are greatly liable to disorder by frost, dust, and other causes.

My invention seeks to overcome the pumping of rack-and-pinion lamps, as Well as those of other types, by simple means and without recourse to dash-pots. To this end I have conceived the simple expedient of separating the slow-movement gearforregulatingthe descent of the carhonholder from the gearing or mechanism for striking the arc and mounting the slow-movement gear in fixed bearings, so that it has no vertical motion. It thus acts to prevent any sudden descent or pumping down- Ward of the carbon-holder. The pumping upward is resisted by a tension-spring applied to a ratchet and pawl in connection with the slowmovement gear, the resistance being sufticient to prevent the lifting of the carbonholder by any transitory force or fluctuation ot' current, but insufficient to prevent its being lifted by the full tension of the main-cnrrcnt magnet for striking the arc, or by the operator for inserting new carbons. Either the slow-movenient gear may be the feeding meehanism, or a distinct feeding-gear may be provided. In the former case the shunt-magnet or solenoid will be connected to an arresting device for the slow-movement gear. In the latter case it will be adapted to operate an arresting device for the independent feedinggear, which gear Will thus be mounted in the liftingframe, which is connected to the maincircuit magnet or solenoid.

The accompanying drawings show my invention embodied in two different constructions.

Figure l is an elevation, partly in section, of the essential parts of the lamp; and Figs. 2 and 3 are horizontal sections on the planes of the lines 2 2 and 3 8, respectively. Fig. 4- is an elevation of another construction of lamp, of which Fig. 5 is a horizontal section on the line 5 5 in Fig. d.

I will first describe thc construction shown in Figs. 1, 2, and 3.

Let A designate the upper carbon pencil; A', the lower one; B, the carbon-holder for carrying the carbon A; C, the slow-movement gear77 as a whole; D, thelifting-gear for striking the arc as a whole; 1I, the main-circuit magnet or solenoid; S, the shuntcircuit magnet or solenoid, and F the frame-Work of the lamp.

The carbon-holder B consists, as usual, of a tubular rod with a cog-rack, b, formed on one side, with which meshes the pinion a of the slow-movement gear. This pinion is mounted on a small shaft or spindle, c, on which is also mounted a toothed Wheel or gear, d. The pinion a communicates with the gear d through a ratchet and patri, so that the carborrliolder cannot descend Without turning the gear, but may ascend While the gear remains stationary. In the construction shown ICG the ratchet-wheel e is fixed to or made in one` piece with the pinion, while thepawlfis'pivoted to the gear d. The tensiou-springg of the pawl is also fastened to the wheel d, with its free end pressing against the pawl and foreing it toward the ratchet-wheel. This press. nre ofthe spring generates a certain resistance to the backward turning of the ratchet, on account ot' the Obliquity of the ratchet-teeth which lift the pawl. lt is desirable that the tension ot' this spring be made adjustable, in order that the resistance offered by the ratchet to the upward movement of the carbon-holder may be regulated to a nicety. This, however, may be done in the original construction of the instrument.

The gear d meshes with a pinion, h, on a little shaft or spindle, i, on which is fixed a toothed escape-Wheel, j. With this meshes an anchor, k, on a spindle, Z, on which is fixed a vibrator, m, or short pendulum acting as an cscapement. The mechanism thus described constitutes the slow-movement gear for retarding the descent ot the carbon-holder. When the carbon-holder is released, its weight acts upon this train of gearing, rotates the wheels, and vibrates the escapement, which acts to limit the rotation of the wheels, and consequently to prevent the descent of the carbonholder at too rapid a rate.'

The spindles c, i, and lof the slow-move` ment gear have bearings in a frame, F,which is fixed to the frame F, instead of being a pivoted frame movable up and down, as heretofore. ln the construction here shown the slow-movement gear constitutes also the feeding mechanism. The armature-lever n ofthe shunt-magnet S extends beyond its pivotal axis and terminates at p over the'vibrator on in such position that when the magnet relaxes and the armature is drawn up by the retraeting-spring o this end p descends into the way of the vibrator m and intercepts its movement. The end p may constitute astop by dropping into the path of the upper end of the vibrator, or it may constitute a brake by extending over the upper end ofthe vibrator a-nd dropping down thereupon when released.

The lifting-gear D for striking the are consists of a pinion, q, which meshes with the rack b on the carbon holder, a' spindle, r, for this pinion,'an escape-wheel, s, on this spindle, and an escapement anchor, t, on a spindie, u, on which is fixed a vibrator, c. This mechanism is hung in a frame or lever, E, which affords bearings for the spindles r and u. This frame is pivoted or fulcrumed between screws a' rc, is countcrweighted at E', and at its opposite end is jointed to the core M of the main-circuit solenoid M; or if a magnet be used instead of a solenoid the free end of the frame E will bear its armature.

It is desirable, but not essential, that the lifting-gear be provided with a ratchet and pawl interposed between pinion qand escapewheel s, to facilitate the lifting of the carbonholder in order to insert new carbons.

The operation is as follows: Vhe'uV the current is first turned ou, it excites the solenoid M, which draws up its core, and thereby lifts the free end of the frame E, and with it thelifting-gear D andthe carbon-holder B, thus separating the carbon pencils and establishing the are. VVhilethe carbon-holder is thuslifting the pinion a and ratchet-wheel c of the slow-movement gear turn backward. When the carbonholder is lifted, it is caught by this gear and held elevated, since this gear is prevented from operating by the Stopp. This continues until the are burns too long, whereupon the shunt-magnet acts, the stop p is lifted, the slow-movement gear is thereby freed, and the carbon-holder descends slowly until the are is shortened to its normal length, when the shunt-magnet releases its armature and the Stopp dropsand again holds the gear C. It' the current should be momentarily interrupted, thus extinguishing the are., the solenoid M would release its core and the frame E would drop. On the resumption of the current it would excite the shuntmagnet,thereby releasing the slow-movement gear and p'ermitting the carbon-holder to run down until the carbons touched, when immediately the solenoid M would act to re-establish the are. lIf a quicker action be desired,the frame E may be provided with a screw-leg, w, Fig. 1, which, on the dropping of the frame E, will strike the armature-lever and depress it to the same effect as though the shunt-magnet were excited, thus releasing the stop p and permitting the carbon-holder to run down and re-establish the main circuit. As the carbonholder feeds downward,it rotates both systems of gearing and vibrates both vibrators m and c. The lifting-gear normally does not materially resist the descent of the carbon-holder, since its escapement works very freely and is not geared up, as in the slow-movement gear. In the act of lifting the anchor t engages the wheel s lirml y and acts for an instant as a pawl, but immediately the lifting-pressure is relaxed it becomes a free escapement. The slow-movement gear effectually prevents any pumping downward of the carbonholder, since the escapement is so adjusted as to permit of movement no faster than that which is desirable in feeding-namely, a movement Somewhat more rapid than the rate of consumption of the carbons, but not rapid enough to produce any iiickering or flashing of the light. The slow-movement gear also effect ually resists any pumping upward of the carbon-holder by reason of the tension of the spring g of the ratchet and pawl, as already described. This tension should be sufcient to resist any sudden lifting tendency of less energy than the lifting movement of the maincircuit solenoid, which is nccessarry to establish the are.

Figs. 4 and 5 show a different construction. Here the slow-movement gear C has no function except to retard the descent of the carbon-holder and prevent pumping. Two solen- IOO lIO

IZO

oids, M S, arc employed, pulling oppositely upon one core, which is pivoted to the frame E, as before. This frame bears the liftinggear, which in this construction acts also as the feeding-gear. rIhis gear consists of pinion q, (meshing with rack 1),) mounted on spindle r, gear-wheel s on the same spindle, connected to the pinion through the medium of a ratchet and pawl, in order to permit the free lifting of the carbon-holder, a pinion, t', gearing with said wheel and fixed on a spindle, a', a brake-wheel, u', on said spindle, and a iiy or fan, f, also on said spindle. Above the frame E is pivoted a brake-lever, G, which is drawn by a tension-spring, g', against an adjustable stop, h. As the frame E rises above the position shown, the brake-levcr yields and rises with it, holding` the brake-wheel from revolving; but when the frame descends below the position shown the brake-wheel is freed from the brake, and the gear is free to revolve, limited in its speed only by the fan f. At Starting, the solenoid M lifts the core, frame, and carbon-holder high enough to establish the are and to bring the friction-wheel against the brake. As the are lengthens, the shuntcoil S pulls more and more, until finally it draws down the frame E until the wheel is freed from the brake, whereupon a feeding of the carbonholder takes place until the are is sufficiently shortened, when the shunt-coil relaxes and the main coil again lifts the frame slightly, thus carrying the wheel against the brake and stopping the feed.

I have thusshown two alternative and equivaient methods ofoperation-viz., rst, controlling the feed by the action of the shunt-magnet on the slow-movement gear, and, second, controlling the feed by the opposing action of a main and shunt solenoid (or electro-magnet) on the lifting-gear. In the former case it is the slow-movement gear, and in the latter case it is the lifting-gear that constitutes the feeding mechanism. I have also shown two equivalent methods of retraction-viz., a vibrating eseapemcntand a fan or flier-and two equivalent methods of stopping and feeding-viz., by a stop and by a brake-and by moving the stop or brake to or from a stationary vibrator (or wheel) on the one hand and moving a wheel (or vibrator) toward or from a stationary brake or stop on the other.

My slow-movement gear may be used in other types of electricare lamps, being in general a substitute for dash-pots.

I claim as my inventionl. In an electric lamp, the combinatiomwith a magnet in the main circuit and gearing counected therewith and actuated thereby for raising the carbon to establish the arc, of a magnet in a shunt-circuit, and independent slow-motion gearing mounted in a stationary frame and connected with the shunt-magnet and adapted to regulate the descent of the carbon, substantially as set forth.

2. The combination, with a rack and-pinion arc lamp, of a slow-movement gear meshing with a rack on the carbon-holder, mounted in fixed bearings and adapted to resist any tendency to downward pumping of the carbonholder, and a ratchet and pawl forming part of said gear, and having a tension-spring for the pawl of strength sufficient to resist transitory tendencies to upward pumping of the carbon-holder, but insufficient to resist the lifting force of the main-circuit magnet for establishing the are, substantially as set forth.

3. In an electricarc lamp, the combination, with the carbon holder or rod, of two separate gearings engaging with the carbon rod, one of said gearings being a slow-motion gear and mounted in a stationary frame and the other constituting a lifting-gear and mounted in a movable frame, and a main magnet included in the arc circuit and a shunt-magnet included in a constantly-closed shunt-circuit around the arc, said magnets and gearing being combined and arranged to automatically establish the arc, regulate its length, and feed the carbon, substantially as set forth.

Inwitness whereof l have hereunto signed my name in the presence of two subscribing witnesses.

GUSTAV PFANNKUCHE.

lVitnesses:

WILLrAM l. )loULToN, Oscar: FAULHABER. 

